Ultrasound Guided Percutaneous Ethanol Ablation of Benign Thyroid Nodule: A Study From a Tertiary Hospital in Eastern India

Abstract Introduction: Ultrasound guided percutaneous ethanol injection (PEI) of benign thyroid nodule is an easy and effective procedure particularly in cystic and predominantly cystic nodule. Aims: To evaluate efficacy and safety of PEI in managing purely cystic and mixed cystic and solid thyroid nodules. Materials and Methods: Patients of either sex presented with solitary purely cystic benign thyroid nodule, solitary benign mixed with predominantly cystic (>50% of total volume) thyroid nodule, solitary benign mixed with predominantly solid (>50% of total volume) thyroid nodule, solitary solid thyroid nodule were included in this study. Patients who had a nodule BETHESDA 3 and above, pregnancy, patients with critical or terminal illness, patients with other malignancies, multinodular lesions of thyroid, patients with raised T3, T4 and/ or suppressed TSH level were excluded from the study. One hundred sixty patients presenting with thyroid nodule were initially evaluated with thyroid function test and USG. Only those patients with euthyroid solitary thyroid nodules are subjected for fine needle aspiration (FNA). Nodules under BETHESDA 2 are considered for US guided percutaneous ethanol injection (PEI). One hundred twenty-three patients were excluded because of various reasons. Finally ethanol ablation was done in 37 patients. Benign, purely cystic and mixed thyroid nodules were aspirated under ultrasonography guidance. Sterile absolute alcohol (99.99%) (50% of volume aspirated/ maximum 10 ml) was injected and reviewed after 2, 5and 7 months. In case of solid nodule alcohol (50% of nodule volume) was injected. A reduction in volume is calculated at each follow up visit. An adequate response is considered as ≥50 percent reduction in size from baseline after 7 months. If the reduction is <50%, then a second session of absolute ethanol injection is given. Again, patients were similarly followed up after 2, 5 and 7 months. Results: Thirty seven patients underwent PEI. Thirty three patients were considered for final analysis (4 lost to follow up). Response rate of PEI for purely cystic nodule was 100.0% and the overall response rate for mixed nodule was 53.57%. None of the solid nodule responded to PEI even after second session. Among the responder in the mixed nodules, 93.33% responded after first session of PEI. Minor complications like headache occurred in 54.1% patients in the first session. Transient pain at injection site were complained by 86.5% and 37.8% patients in the first and second session respectively. Nausea and vomiting were complained by 18.9% and 16.2% patients in the first and second session respectively. Conclusions: PEI is an effective and safe for purely cystic and mixed thyroid nodules. It is a relatively safe and less invasive procedure from management of benign solitary cystic and mixed thyroid nodules.